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Indonesia invites investment in 35 GW hydropower
Estimated reading time: 4 minutes · Last updated:
Indonesia is seeking investor participation to develop 35 GW of potential hydropower, split between a 23 GW Mamberamo River project in Papua and roughly 12 GW on the Kayan River in Kalimantan. The Indonesian Minister of Energy and Mineral Resources highlighted those two river projects; Antara News reported the Mamberamo figure on 22/09/2026. Enerdata's data show coal accounted for 67% of the country's power mix in 2025, with hydropower at 7% and CO2-free generation representing just over 13% that year. The 2025 National Energy Policy (KEN) now targets a 19–23% renewables share of primary energy by 2030 and sets an interim 2025 range of 17–19%. This summary uses Enerdata's figures, as first reported by Enerdata.
Key takeaways
- Project scale: Indonesia is promoting 35 GW of hydropower potential, comprising 23 GW at Mamberamo (Papua) and around 12 GW at Kayan (Kalimantan).
- Current generation mix: Enerdata records coal at 67% of Indonesia's power mix in 2025, followed by gas at 15% and hydropower at 7%.
- Low zero-carbon share: CO2-free generation accounted for just over 13% of the power mix in 2025, Enerdata data show.
- Policy targets: The 2025 National Energy Policy (KEN) sets a 19–23% renewables share in primary energy by 2030 and lowers the 2025 interim target to 17–19%.
Table of contents
Which projects add up to 35 GW and who announced them
The two river schemes the ministry promoted together amount to the 35 GW headline figure. The Mamberamo River Hydropower Plant (PLTA) in Papua is cited with a 23 GW potential capacity, a figure reported by Antara News on 22/09/2026. The Kayan River scheme in Kalimantan is presented with an estimated potential of around 12 GW.
The call for investor participation was made by the Indonesian Minister of Energy and Mineral Resources; the announcement did not name developers, tender dates or financing partners. Those implementation details — who will bid, how projects will be packaged, and timelines — were not included in the figures cited.
What these projects mean for Indonesia's generation mix
On paper the 35 GW potential is large relative to existing hydropower: Enerdata records hydropower at 7% of generation in 2025. Bringing even a portion of the Mamberamo and Kayan capacity online would alter regional generation balances, but the material makes no claims about deliverable output, staging or connection capacity.
Enerdata's country-level data underscore the scale of the challenge: coal provided 67% of power in 2025 and CO2-free sources together accounted for just over 13%. That contrast explains why the ministry is seeking investor interest, yet the gap between technical potential and built, grid-connected capacity remains unquantified in the available figures.
Policy targets, revisions and the implied shortfall
The government's updated National Energy Policy (KEN) from 2025 sets a renewables share of 19–23% in primary energy by 2030 and lowers the near-term 2025 objective to 17–19%. That adjustment replaces the prior 2014 KEN aim of a flat 23% by 2025, signalling a recognition of slower deployment rates.
Enerdata's figures imply a material policy gap if coal remains at 67% and CO2-free generation stays near 13%. The source does not link the Mamberamo or Kayan projects to specific contributions against the KEN targets, so whether the two river schemes are intended to close that gap, or to serve regional needs, is not specified.
| Project | Region | Potential capacity |
|---|---|---|
| Mamberamo River Hydropower Plant (PLTA) | Papua | 23 GW |
| Kayan River hydropower project | Kalimantan | around 12 GW |
How the case for and against rapid build-out stacks up
The case for
- Large technical potential: the two projects total 35 GW, which if developed at scale would materially expand Indonesia's hydropower fleet compared with current capacity shares.
- Policy alignment: the 2025 KEN raises the profile of renewables with a 19–23% by 2030 target, creating a framework that could prioritise project approvals and attract investors.
The case against
- Coal dominance: with coal at 67% of generation in 2025, displacing fossil output at scale requires rapid and sustained deployment that the material does not document.
- Unspecified delivery details: the announcement lacks timelines, financing plans and grid-integration commitments, so potential capacity may not translate into delivered generation.
What to be careful about
- No tender or financing timetable provided for Mamberamo or Kayan, leaving execution risk high.
- Grid connection and regional transmission capacity are not quantified for the projects, so realised output could be constrained.
- Social and environmental approvals are not referenced in the figures; permitting risk could delay or downscale projects.
The bottom line
The ministry's promotion of 35 GW of hydropower potential highlights a technical resource that could support Indonesia's long-term decarbonisation goals. Enerdata's figures, however, show a system still overwhelmingly supplied by coal — 67% in 2025 — and only modest CO2-free shares today. The announcement names two very large river projects but omits the commercial, permitting and grid-integration details that would determine whether that potential can be realised at scale. Tracking formal tender schedules, financing arrangements and the KEN's operational measures will be essential to judge whether these river schemes move from potential capacity to actual clean generation.
What to watch
- Watch for published tender schedules or financing plans for Mamberamo and Kayan; no date has been set.
- Watch for government updates to KEN implementation that specify how Mamberamo and Kayan would contribute to the 19–23% renewables target by 2030; no date has been set.
Frequently asked questions
How is the 35 GW total divided between projects?
The 35 GW headline is comprised of a 23 GW potential at the Mamberamo River Hydropower Plant (PLTA) in Papua and about 12 GW at the Kayan River project in Kalimantan, as cited in the source.
How dominant is coal in Indonesia's power mix today?
Enerdata reports coal supplied 67% of Indonesia's power mix in 2025, with gas at 15% and hydropower at 7% that year.
What are Indonesia's renewables targets under the 2025 KEN?
The 2025 National Energy Policy (KEN) sets a renewables share of 19–23% in primary energy by 2030 and reduces the near-term 2025 target to a 17–19% range.
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